Expand Windows PATH tag to Unix-Based and Inspired OSes

[Kronifer]

Currently, we only have a tag for the windows PATH variable. I suggest we expand this tag to explain what the path is, and maybe explain or give a guide on how to alter it.

[wookie184]

I don't think we should extend the windows path tag as it's already quite long. We could add a separate tag to explain how to modify the PATH, although that differs depending on OS so we could end up with quite a long tag, and i'm not sure how useful it would actually be.

One option would be to have:

• A guide on the site explaining how to add Python to path on windows, with the method here https://github.com/wookie184/python-guides/blob/main/windows/add-to-path.md, possibly as well as detailing how to add it to path manually, and maybe suggesting reinstalling if all else fails with a link to a page on how to install it properly.
• A py-launcher tag, similar to the current windows-path tag (and remove the windows-path tag), which explains how to use the py launcher. Would link to the site page.
• A general path tag, which just explains what PATH is, and links to the site page for how to change it on windows, and maybe another page for changing it on unix systems.

I'm not sure what the use of a tag explaining how to change the PATH on a unix system would be in the context of Python (as I don't use a unix system). Is it common for users to have a Python install on linux but not to be able to access it because it isn't on PATH? From what i'm aware, the main recommended ways of installing Python would be through a package manager, or pyenv, both of which would usually handle PATH modification for you.

[Kronifer]

@wookie184 I'd probably just do the path tag